Iredell-Statesville Schools Integrated Math I Core Plus - Course 1 Unit 5 Guide Exponential Functions Using this guide: It is the expectation that all teachers will have their classes complete all items listed in this guide, in the order in which it is presented, and completed in the labeled time frame. At the teacher’s discretion, additional examples, problems, assignments and assessments may be added to this guide. In the rare instance in which an investigation has already been covered, the teacher should cover the same topic and remediate or extend the students’ learning in the same time frame. We will be seeking feedback on the guide as we progress through the year. Unit 5 Planning Guide (p. 289B) Exponential Functions develops student ability to recognize and represent exponential growth and decay patterns, to express those patterns in symbolic forms, to solve problems that involve exponential change, and to use properties of exponents to write expressions in equivalent forms. Topics include exponential growth and decay functions, data modeling, growth and decay rates, half-life and doubling time, compound interest, and properties of exponents. NC Math I Standards covered in this unit: Still working on this, but coming soon! Lesson 1: Modeling Linear Relationships Launch: Students should start on p. 291, reading the first page and looking at all charts, graphs and data provided. The teacher then should lead a class discussion of the “Think About the Situation.” Use these questions to formatively assess the needs of your class and make adaptations as needed (You will get better at this as you become more familiar with this curriculum). This is not a time to teach concepts forgotten, only a time to assess the students’ needs. The investigations that follow will teach or reteach these concepts. You can explain to students that they should be able to figure out the complete answers when they complete the lesson. TEACHER OPTION: The Core Plus program puts Properties of Exponents in Lesson 1 Investigation 5 and Lesson 2 Investigations 4 and 5. It is your choice whether you want to pull those investigations out and create an Exponents lesson before you begin the Growth and Decay lessons. Explore: Investigation Topic Description Investigation 1: Counting in Tree Graphs (p. 291) Students will recognize and understand CYU p.294 exponential patterns using NEXT=b*NOW OYO p.307 #2, 4, 17-19, 25 (writing and y=bx extension), 30 (extension) 2 days Students work with exponential functions CYU p.298 that start at other numbers then 1. OYO p.307 #5-6, 21-22, 26, 31 (extension), Students will recognize the implications 38 (Review) of exponential growth. 1 day (Before the investigation use p. 319 #35,36 as a warm up.) Share, Summarize and Apply Time Frame The whole investigation will need be completed, except #4. *Use Pay It Forward video clip on youtube.com * Myth Busters Video- Paper Folding Activity could be used to launch this lesson (as well as Lesson2) Investigation 2: Getting Started (p. 295) The whole investigation will need be completed *#3 - students don’t need to do all 4 tables (pick 1 or 2) Investigation 3: Compound Interest (p. 298) The whole investigation will need be completed Students will work with exponential functions in which the growth rate is a fraction. CYU p.301 2-3 days OYO p.307 #7-8, 23, 33 (Extension) Compound Interest *Split up #5 so each group has to explain it to the whole group *Supplement with worksheet on compound interest Investigation 4: Modeling Data Patterns (p. 302) Students will learn to find an exponential model to fit given data. The whole investigation will need be completed Students will be able to recognize when to use an exponential model. STM p. 303 1 day OYO p.307 #11-12, 24, 26-27 (Supplement with worksheet) *Discuss correlation coefficient and how to set up diagnostic *Split up problems #1 and 2 in Investigation #4 between the groups and then have groups share with class Investigation 5: Properties of Exponents I (p.304) Students will discover (rediscover) three basic exponential laws. CYU p.306 OYO p.307#13-16, 28, 29 The whole investigation will need be completed *Need supplemental lesson on proving properties of exponents (stress expanding to prove.) Suggestion: Split among groups: Product of powers, Power of a power and Power of a product 1 day Assessment Vocabulary to be used in this assessment: Exponential Growth (increase), Exponential Decay (decrease), Initial Value, Compound Interest, Interest Rate, Regression, Correlation Coefficient Lesson 2: Exponential Decay Launch: Students should start on p. 322, reading the first page and looking at all charts, graphs and data provided. The teacher then should lead a class discussion of the “Think About the Situation.” Use these questions to formatively assess the needs of your class and make adaptations as needed (You will get better at this as you become more familiar with this curriculum). This is not a time to teach concepts forgotten, only a time to assess the students’ needs. The investigations that follow will teach or reteach these concepts. You can explain to students that they should be able to figure out the complete answers when they complete the lesson. Explore: Investigation Topic Description Substitute Investigation #1 with Paper Folding/M&M/Rhino Activity Share, Summarize and Apply Time Frame *Students will complete handout for Rhino Activity 1 Day for activities .5 of next day for discussion of Rhino CYU p. 329 1 Day *Teacher leads Paper folding activity as a class discussion. *Students work in groups to complete M&M activity. *An option is for the teacher to bring in half-life as a discussion point with students after M&M activity is complete. Investigation 2: Medicine and Mathematics (p.326) The whole investigation will need be completed. *Teacher will need to discuss what is halflife is with students. (if not done on previous day). The students will extend their understanding of exponential decay by looking at tables, graphs, and rules. Interpretation of fractional exponents OYO p.338 #4-5, 20 *Teacher will need to clarify medical terms used in the problems. Investigation 3: Modeling Decay (p. 330) The whole investigation will need be completed. The student will create exponential models to fit given data. STM p. 331 1 Day OYO p.338 #9, 11, 42 Students will compare models created by logic to those created with technology. *Will need 100 coins or 100 of one item and an area split into two parts *Can be done as a class. *Optional if needed for lower students. Investigation #4: Properties of Exponents II (p.332) Students will extend their knowledge of the properties of exponents. CYU p.334 1.5 Days OYO p.338 #12-16 *Use the problems from 1, 3, 7 to develop quotient and negative properties of exponents. *Use 2a, 2b, 4a, 4b, 5, 8a for student depth of knowledge and discussion. Investigation 5: Square Roots and Radicals The students will build and use an (p.335) understanding of rewriting radicals expressions. *Use the problems from 1, 2, 5 to develop ideas of radicals and rational exponents Connecting square roots to fractional *Use 4,6 for student depth of knowledge exponents. and discussion *Supplemental Resources on Quotient Rules and Negative Exponents CYU p.337 a-c 1 Day *Supplemental Resources on radicals and rational exponents Assessment Coming Soon! Vocabulary to be used in this assessment: Half-life, Exponential Decay, Radicals, Rational Exponents, Powers of a Fraction, Quotients of Powers, Negative Exponents, Now-Next Lesson 3: Looking Back Launch: This is a review lesson, so there is not a standard launch. Explore: Investigation Topic Description Share, Summarize and Apply Time Frame Looking Back (p. 232) The students will extend their understanding of exponential decay by looking at tables, graphs, and rules. CYU p.359 1-2 days This is a review lesson that relates the previous three lessons. Complete the parts of this lesson that your class needs for review. Interpretation of fractional exponents OYO p.338 - Use any of the suggested problems from the Unit 5 Planning Guide (p. 289B) from the previous lessons in this Unit. The student will create exponential models to fit given data. Students will compare models created by logic to those created with technology. Students will extend their knowledge of the properties of exponents. The students will build and use an understanding of rewriting radicals expressions. Connecting square roots to fractional exponents. Assessment: Coming Soon! Vocabulary to be used in this assessment: Exponential Growth (increase), Exponential Decay (decrease), Initial Value, Compound Interest, Interest Rate, Regression, Correlation Coefficient, Half-life, Exponential Decay, Radicals, Rational Exponents, Powers of a Fraction, Quotients of Powers, Negative Exponents, Now-Next